Comentario sobre Números 33:40

וישמע הכנעני AND THE CANAANITE HEARD This is stated here to tell you that Aaron’s death was indeed the news he heard — that the clouds of glory that until now had protected Israel had departed, and he therefore believed that liberty was now given to wage war against Israel. It is on this account that this is again recorded here (see Rashi on Numbers 21:1) (Rosh Hashanah 3a).

וישמע הכנעני, this too was a credit for them in that this time they did not say: “let us appoint a new leader and return to Egypt.” (Compare Numbers 14,4 when they did) This time they were not afraid of facing war and battle.

וישמע הכנעני מלך ערד, “the Canaanite, i.e. the King of Arad heard.” This verse follows mention of Aaron’s death to teach that when the Canaanite noticed that Aaron had died and that the protective cloud-cover over the camp of the Israelites had disappeared, they assumed that it was now permissible to attack this nation.